set ANSI_NULLS ON
set QUOTED_IDENTIFIER ON
GO
create FUNCTION [dbo].[FunSunDate](
	@DS datetime  )
	
RETURNS char(8)
AS
begin
		if @ds is null set @ds=getdate()
        declare @YY int
        declare @MM int
        declare @DD int
        declare @OrginalDate datetime
        declare @CurrentDate datetime
        declare @InterVal int
        declare @Kabiseh int 
		Declare @ConvertedDate char(8)
		set @kabiseh=0

        set @YY = Year(@DS)  
        set @MM = Month(@DS)
        set @DD = Day(@DS)
        set @CurrentDate = convert(datetime,str( @mm) + '/' + str( @dd)+ '/' + str( @YY) ,101)
        set @OrginalDate = convert(datetime,'01/01/'+str( @YY)  ,101 )
        set @DD = DateDiff(day, @OrginalDate, @CurrentDate)

        set @YY = @YY - 1900
        set @InterVal = 287

        If (((@YY - 1) % 4) = 0) --eng kabiseh
            set @Kabiseh = 1
        
		set @DD = @DD + @InterVal + @Kabiseh
        set @YY = @YY - 22
        set @DD = @DD - 1  --baraye inkeh rooz 30 v 31 ham dashteh bashim
        If @DD > 365  
            begin
				set @DD = @DD - 365 - @Kabiseh
				set @YY = @YY + 1
			end 
        If @DD >= 186 
			begin 
				set @MM = 6
				set @DD = @DD - 186
				set @MM = @MM + floor((@DD / 30)) + 1
				set @DD = (@DD % 30)
			end
        Else
			BEGIN
				set @MM = floor((@DD / 31) ) + 1
				set @DD = (@DD % 31)
	        End  
        set @DD = @DD + 1
        set @ConvertedDate= str( @YY,2) + '/' + right('00' + ltrim(str( @mm)),2) + '/' + right('00' + ltrim(str( @dd)),2)
		return @ConvertedDate

end